Search  for anything...
thermomate

Tankless Water Heater Electric 27kW at 240 Volt, ThermoMate On Demand Instant Hot Water Heater Up to 6.4GMP, Self-Modulating Energy Saving for Residential Indoor Shower, Draw 114Amp

  • Based on 465 reviews
Condition: New
Checking for the best price...
$339.98 Why this price?
Save $90.01 was $429.99

Buy Now, Pay Later

As low as / mo
  • – Up to 36-month term if approved
  • – No impact on credit
  • – Instant approval decision
  • – Secure and straightforward checkout

Ready to go? Add this product to your cart and select a plan during checkout.

Payment plans are offered through our trusted finance partners Klarna, Affirm, Afterpay, Apple Pay, and PayTomorrow. No-credit-needed leasing options through Acima may also be available at checkout.

Learn more about financing & leasing here.

Selected Option

Free shipping on this product

FREE 30-day refund/replacement

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

Availability: In Stock.
Fulfilled by Amazon
Arrives Sunday, Mar 8
Order within 4 hours and 1 minute
Available payment plans shown during checkout
Protection Plan Protect Your Purchase
Checking for protection plans...

Style: 27kW


Features

  • [Important] - This 27kW Heater Draws max 114Amp currrent which must requiring 3 dedicated Double-pole 40AMP Circuit Breakers using 3 x 8AWG wiring and strongly recommend 200Amp Household Service for stable use
  • [Instant Unlimited Hot Water] - On demand tankless electric water heater, providing hot water in 3 seconds when you need it and as long as you need, eliminating wait time, never run out of hot water again and No More cold shower. Flow Rate 5.27GPM @35F Rise.
  • [Self-modulating Power] - Self-modulating technology regulating the amount of energy required to heat water only when you need it with 99.8% efficient, saving up to 60% on water heating cost comparing to traditional tank water heater. Wall mounted compact size with no water tank, convenient for any spaces, saving floor space and fitting into tight spaces.
  • [Easy Installation & Safety Protection] - ETL certified with overheating protection, auto stop heating when detecting no water, quality workmanship for leakage protection
  • NOTE - Make sure this water heater is the correct size for your hot water need: 27kW 208 ~ 240V (adjustable) draw max 114Amp; Required breaker: 3 x Double-POLE 40AMP; Wire gauge 3 x 8AWG; Unit size 17.12" x 13.12" x 3.12"; Water connection 3/4" NPT

Brand: thermomate


Power Source: 208~240V Hardwire


Product Dimensions: 13.12"W x 17.12"H


Special Feature: Instant hot water, Leaking free & Maintenance free heating element


Color: Gray


Brand: ‎thermomate


Product Dimensions: ‎13.12"W x 17.12"H


Special Feature: ‎Instant hot water, Leaking free & Maintenance free heating element


Color: ‎Gray


Wattage: ‎27 KW


Voltage: ‎240 Volts (AC)


Maximum Flow Rate: ‎5.27 Gallons Per Minute


Maximum Temperature: ‎140 Degrees Fahrenheit


Heat Output: ‎27 Kilowatts


Efficiency: ‎High


Maximum Operating Pressure: ‎150 Pound per Square Inch


Mounting Type: ‎Wall


Is Electric: ‎Yes


Manufacturer: ‎thermomate


Item Depth: ‎3.12 inches


UPC: ‎750139327607


Manufacture Year: ‎2024


Part Number: ‎ET270


Item Weight: ‎21.7 pounds


Item model number: ‎ET270


Size: ‎240V/27kW


Amperage Capacity: ‎114 Amps


Maximum Power: ‎27 Kilowatts


Installation Method: ‎Wall-Mounted


Temperature Range: ‎80-140 Degrees Fahrenheit


Certification: ‎ETL


Special Features: ‎Instant hot water, Leaking free & Maintenance free heating element


Included Components: ‎Mount Kit


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: January 23, 2021


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Mar 8

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Great Product
Style: 27kW
Review Image by Randy Johnson Randy Johnson
This tankless water heater offers excellent quality at an exceptional price. Installation was simple, and it has performed flawlessly from day one. What stands out most is the noticeable reduction in my electricity bill since switching to this system. In just two years, it has more than paid for itself. I took a chance moving from a traditional water heater to a tankless model, but it turned out to be one of the best decisions I’ve made. ... show more
Reviewed in the United States on February 5, 2026 by Randy Johnson Randy Johnson
    • Awesome
Style: 27kW
Works great. These stand behind what they sell.
Reviewed in the United States on January 7, 2026 by rick
    • Premium product
Style: 27kW
Arrived super fast and packaged nicely. I have installed a few of these units and wanted to get one for myself to truly be able to recommend to my customers. Took about 3 hrs to install with removal of a standard 40 gallon tank. Ran all the electrical needed for power supply and got to work on the piping. I ended up installing a cheap sediment filter on the supply just to try and help keep the heat exchanger clean as much as you can with a cheap filter. I do plan to install a true water softener/filter in the very near future. I would like to try and sell it as a package deal if it works out well. Setup was super simple just like the other units. Very easy to maintenance. It does not come with the flush valves but they are easily ordered separate or you can get them at the big box stores. High quality materials and super super simple settings. Nice digital display tells you the current water temp and a small red light shows its heating. I did install an energy monitor on all 3 circuts to see what my true usage is and its actually very little. In 3 weeks about 55kwhs total. We use 120°F for our setpoint. I would definatly recommend this to anyone looking for a quality water heater. ... show more
Reviewed in the United States on March 16, 2023 by Ashley & Tony
    • Good investment.
Style: 27kW
Review Image by C. E. M. C. E. M.
Went in fairly easy. Just a little drip that went away after a couple days. Does a great job of heating the water. The hot water takes as long as the tank heater to get to your spigot but the difference is that you don't run out like with the tank heater. We can now fill the big tub and take long back to back showers. It cost me a fortune because I did not have enough space in my service for 6 #8 wires 3 double 40a breakers. But my panel was due for upgrade anyway. I put mine right into the old tank closet. I was concerned that the documents called for 12" clearance at the sides. I only had about 8" but I have noticed no great heat to the sides. I hope it lasts a long time but I am pleased now. ... show more
Reviewed in the United States on July 28, 2023 by C. E. M. C. E. M.
    • Good buy
Style: 27kW
Pumps out hot water perfectly, even woth 2 showers and a washer machine going
Reviewed in the United States on September 9, 2025 by david
    • 13 months later unit will not heat
Style: 27kW
This unit didn’t provide 5 consistent gallons a min when it was 105 degrees outside let alone 5 gallons per min at 35 degrees. It did however work well enough. Until last week. Power went out and when it came back on unit wouldn’t heat past 73 degrees Fahrenheit. 24/7 tech support????? I can’t even get them on the phone, I’ve been with out hot water almost 1 week and have called multiple times. I bet they well call aug 8th of next year when there limited warranty expires. If you can’t afford a better hot water heater. This is for you. I don’t regret my purchase. The price was low enough to cover 13 months of service. I’m sure it’s a simple fix, just sucks I’ll have to void my warranty because I can’t get ahold of someone ... show more
Reviewed in the United States on October 11, 2023 by Richard l brown
    • Great item
Style: 27kW
Review Image by Oneil Oneil
Review Image by Oneil Oneil
Review Image by Oneil Oneil
Review Image by Oneil Oneil
Review Image by Oneil Oneil
Review Image by Oneil Oneil
Review Image by Oneil Oneil
Review Image by Oneil Oneil
So far so good installation was easy. I have it set at 120 degrees and I am happy with the continuous amount of hot water it provides during washing clothes and taking a shower. I swapped out multiple of my big old breakers and use double poles to make space in the panel.
Reviewed in the United States on July 23, 2024 by Oneil Oneil
    • Just installed and I love it!
Style: 27kW
Review Image by T E Marcon T E Marcon
This was a replacement for a tankless system that was 16 yrs old. Installed today and I just had the best shower ever. Of course, I've been without hot water for a week, so that might not mean much. We also added hot and cold water service valves and a pressure relief valve. Should be a nice incentive when I sell the house. ... show more
Reviewed in the United States on April 20, 2024 by T E Marcon T E Marcon

Can't find a product?

Find it on Amazon first, then paste the link below.
Checking for best price...